Green’s Dictionary of Slang

1. the nose.

1785, 1788, 1796		Grose Classical Dict. of the Vulgar Tongue.
c.1810		‘The Blind Sailor’ in Holloway & Black I (1975) 30: A splinter knocked my nose off, / My bowsprit’s gone, I cries.
1825		N.-Y. National Advocate 14 Nov. 2/3: There was considerable claret drawn [...] dominos shattered, bowsprit twisted away, and hulks otherwise damaged, till neither party was able to stand on his pins.
1838		D. Jerrold Men of Character I 245: ‘Now you’re so like him – ha! ha! isn’t it his very bowsprit?’ and the humourist pointed his finger to the nose of Runnymede.
1848		Flash Dict. in Sinks of London Laid Open.
1881		Trumble ‘On the Trail’ in Sl. Dict. (1890) 43: If you don’t stow your winds I’ll put your bowsprit in parenthesis.
1905		Marvel III:53 2: That bloomin’ bowsprit of yourn.
1931		(con. 1918) E.W. Springs Rise and Fall of Carol Banks 167: Carol came into the club one day with the reddest nose [...] ‘Why the flaming bowsprit?’ I inquired.

2. the penis, esp, when erect.

1741		‘Captain Samuel Cock’ A Voyage to Lethe n.p.: His Grace the Duke of M— is master of a noble tall frigate, and used to penetrate with his bowsprit even into the privy garden of the palace.
1834		‘Jack Junk’ in Flash Minstrel! in Spedding & Watt (eds) Bawdy Songbooks (2011) I 113: Cried Jack, if you don’t both heave to, / I’ll run my long bowsprit thro’ you! / Said Molly — that’s the man will do.
1897		School Life in Paris 107: Causing his bow-sprit to slide very slowly onwards into its heaven.
1965		Guild Dict. Homosexual Terms 5: bowsprit (n.): An erect penis; because it sticks out like the bowsprit on a ship.
1972		B. Rodgers Queens’ Vernacular 103: erection [...] bowsprit (rare).
1984		Partridge DSUE (8th edn) 126/1: ca. 1820–1880.